Photo transducer circuits have previously been used to convert mechanical position into electrical signals. A typical application of such a transducer is in a pressure gauge as described in U.S. Pat. No. 4,109,147 to Heske. The patent to Heske shows a transducer circuit which produces a digital output through a comparison of the outputs from two photo receivers.
Electronic instrumentation, which records parameters such as pressure, frequently require that the output signal from the transducer comprise a current ranging between minimum and maximum values. The transducer must produce a current output which is proportional to the transducer input information but which varies between a fixed minimum and a fixed maximum amplitude.
Therefore, in view of a need for a defined current range signal for use in instrumentation, there is a need for a transducer circuit for converting position information into an electrical signal having a range between a minimum and a maximum value.